This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. This study is a subcontract of a Conte Center grant based at Yale University. During the reporting period, we used immunoelectron microscopy and quantitative analyses developed in our laboratory to study the distribution of D1 family dopamine receptors (D1 and D5) and signal transduction proteins in normal monkey prefrontal cortex as well as in various interneuron subpopulations. We tested the hypothesis that differential distribution of D1 and D5, receptors that differ in their affinity for the endogenous ligand dopamine, play a role in the inverted U curve relationship between D1 family dopamine receptor stimulation and prefrontal functioning. These studies provided us with a basis for understanding how dopamine controls cognition in primates and how this control might be disordered in schizophrenia.